Argonne National Laboratory

Experimental Physics and
Industrial Control System

2002  2003  2004  2005  2006  2007  2008  2009  2010  <20112012  2013  2014  2015  2016  2017  2018  2019  Index 2002  2003  2004  2005  2006  2007  2008  2009  2010  <20112012  2013  2014  2015  2016  2017  2018  2019 
<== Date ==> <== Thread ==>

Subject: RE: large arrays native element count wrong with Channel Access in EPICS 3.14.12
From: "Jeff Hill" <johill@lanl.gov>
To: "'Andrew Johnson'" <anj@aps.anl.gov>
Cc: core-talk@aps.anl.gov
Date: Wed, 19 Jan 2011 07:55:51 -0700
> I believe the client library clips all array get and subscription
> requests to the array's native element count

that?s correct

Jeff
______________________________________________________
Jeffrey O. Hill           Email        johill@lanl.gov
LANL MS H820              Voice        505 665 1831
Los Alamos NM 87545 USA   FAX          505 665 5107

Message content: TSPA

With sufficient thrust, pigs fly just fine. However, this is
not necessarily a good idea. It is hard to be sure where they
are going to land, and it could be dangerous sitting under them
as they fly overhead. -- RFC 1925


> -----Original Message-----
> From: Andrew Johnson [mailto:anj@aps.anl.gov]
> Sent: Tuesday, January 18, 2011 10:08 AM
> To: Jeff Hill
> Cc: EPICS core-talk
> Subject: Re: large arrays native element count wrong with Channel Access
> in EPICS 3.14.12
> 
> Hi Jeff,
> 
> On Tuesday 18 January 2011 10:31:05 Jeff Hill wrote:
> >
> > PS: Andrew, FWIW and referencing the know problems page, it is actually
> > possible to transfer large arrays w/o the patch. What doesn't work is
> > communication of the native element count when the client connects.
> 
> Right, as long as your client library is 3.14.12 and you're using the
> dynamic
> array sizing feature (which is still rare since it's a new feature).
> However
> I believe the client library clips all array get and subscription
> requests to
> the array's native element count (or maybe it rejects them if too large,
> I
> forget which), so I'm pretty sure that a client application using an
> older
> library version against an unpatched 3.14.12 IOC isn't going to be able
> to
> override the incorrect native count.  I haven't tried it though, so I
> might be
> wrong.
> 
> - Andrew
> --
> If a man is offered a fact which goes against his instincts, he will
> scrutinize it closely, and unless the evidence is overwhelming, he will
> refuse to believe it.  If, on the other hand, he is offered something
> which affords a reason for acting in accordance to his instincts, he
> will accept it even on the slightest evidence.  -- Bertrand Russell



References:
Re: large arrays native element count wrong with Channel Access in EPICS 3.14.12 Andrew Johnson

Navigate by Date:
Prev: Re: large arrays native element count wrong with Channel Access in EPICS 3.14.12 Andrew Johnson
Next: RE: src/ reorganization (merge request) Davidsaver, Michael
Index: 2002  2003  2004  2005  2006  2007  2008  2009  2010  <20112012  2013  2014  2015  2016  2017  2018  2019 
Navigate by Thread:
Prev: Re: large arrays native element count wrong with Channel Access in EPICS 3.14.12 Andrew Johnson
Next: RE: src/ reorganization (merge request) Davidsaver, Michael
Index: 2002  2003  2004  2005  2006  2007  2008  2009  2010  <20112012  2013  2014  2015  2016  2017  2018  2019 
ANJ, 02 Feb 2012 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· Search · EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·